This disclosure relates generally to a fire protection sprinkler and to a method of assembling such a fire protection sprinkler. More specifically, this disclosure relates to a fire protection sprinkler comprising a wrench boss detent and a cooperating clip that provide reliable action and may facilitate assembly of the fire protection sprinkler.
Conventionally, fire protection sprinklers are connected to a conduit that supplies a pressurized fire-extinguishing fluid, such as water. A typical fire protection sprinkler has a base with a threaded portion for connection to the conduit to receive the fluid, and an output orifice to output the fluid to provide fire control and/or fire suppression. The output orifice is sealed by a seal cap, which is held in place by a release mechanism. The release mechanism is designed to release the cap under predetermined conditions, thereby initiating the flow of the fluid. A typical release mechanism includes a latching mechanism and a thermally-responsive element, e.g., a frangible bulb or a fusible link.
Certain conventional fire protection sprinklers have a pair of arms that extend from the base portion and meet at a hub portion to form a frame that supports a deflector plate provided to direct the fluid in the desired directions. Other fire protection sprinklers have the arms supporting a deflector plate directly, without meeting in a hub. A set screw or similar arrangement is provided to apply a pre-tension force to the latching mechanism.
A sprinkler may be listed to comply with the Standard for Safety for Automatic Sprinklers for Fire-Protection Service (UL 199), the Standard for Safety for Residential Sprinkler for Fire-Protection Service (UL 1626), or the Standard for Safety for Early-Suppression Fast-Response Sprinklers (UL 1767), each of which is published by Underwriter's Laboratories, of Northbrook, Ill., United States. UL 199, UL 1626, and UL 1767 include operation lodgment tests to verify that parts released from a fire protection sprinkler upon operation, such as the cap, “ . . . clear the sprinkler frame and [the] deflector to not impair the water distribution pattern . . . .” (UL 199, p. 40F). Certain conventional fire protection sprinklers have arms, a hub, or a deflector that are designed to allow the cap to release from the fire protection sprinkler upon operation without impairing distribution of the fluid. Certain other conventional fire protection sprinklers use an ejection spring to urge the cap away from the fire protection sprinkler upon operation, such as the fire protection sprinkler described in U.S. Reissued Pat. No. 45,377.
In addition, a conventional fire protection sprinkler may be provided with a kick spring to assist in clearing portions of the release mechanism from the path of the fluid upon activation of the fire protection sprinkler. Ensuring that operating elements of the fire protection sprinkler clear the frame and the deflector without getting caught is a major source of frustration for fire protection sprinkler manufacturers.
A fire protection sprinkler may be mounted on a fluid conduit running along a ceiling, and may either extend upward from the conduit, which is referred to as an “upright” configuration, or depend downward from the conduit, which is referred to as a “pendent” configuration. Alternatively, the fire protection sprinkler may be mounted on a wall, at a certain distance below the ceiling, which is referred to as a “horizontal sidewall” configuration. Other configurations exist in which the fire protection sprinkler is oriented horizontally.